Clem 7 - case study
- Engineering design
- Construction and commissioning
The M7 Clem Jones Tunnel – also known as the Clem 7 - is the central part of a 6.8km-long tollway system built for $3 billion. This system links five major Brisbane roads, including the Pacific Motorway, Ipswich Road, Lutwyche Road, the Inner-City Bypass and Shafston Avenue at Kangaroo Point. The M7 Motorway system’s Clem 7 tollway joins Brisbane’s southern suburbs to the north, enabling alternate connectivity to the airport.
Of the Clem 7 tollway, the tunnel component is 4.8km long, making it the longest operating road tunnel in Australia (at the time of construction). It is a ‘twin tube’ construction, with each cylinder carrying two lanes of traffic. At its lowest point, the tunnel is 60 metres below the Brisbane River.
Brisbane City Council determined the need for an additional crossing of the Brisbane River as part of the M7 Motorway, linking South Brisbane to Fortitude Valley in the north. The objective of the tunnel itself was to provide a faster, safer, more reliable choice for cross-city travelers using world’s best practice and technology to satisfy the stringent safety requirements.
The purpose of any transport tunnel control and communications system is to monitor and control all safety subsystems and equipment required to make the tunnel structure as safe as reasonably possible for public use and maintenance activities.
UGL was the principal mechanical and electrical engineering contractor for the Clem 7 tunnel, delivering one of the largest and most complex control and communications systems in Australia. Despite its size and complexity, the system provides a one second response time for each of its 170,000 supervisory control and data acquisition (SCADA) tags, and operates with an availability exceeding 99.995%.
UGL’s scope of work for the Clem 7 project included:
- project management
- procurement/ fabrication
- construction and
The tunnel was built by a joint venture, consisting of Leighton Contractors, Baulderstone, and Bilfinger-Berger. The joint venture engaged UGL to design and construct the tunnel’s mechanical and electrical services, including the control and communications system.
UGL’s integrated development methods provided a single and consistent operator interface for the widely diverse tunnel sub-systems, allowing the safest and most efficient use of the facility for both the public and maintenance personnel.
Formal software architectural definition methods were used to define all the mandatory modules within the complex system. A centralised multi-disciplinary engineering database was used to manage all the necessary design information.
Engineers were assigned responsibility for work in functional areas instead of in software application fields. This innovative departure from routine transport control and communications system development approaches provided advantages in terms of higher accuracy, faster start-up, concurrency, consistency, quicker response to change, traceability, and expanded construction support.
The various sub-systems and equipment which are monitored and controlled by the tunnel control and communications solution that UGL delivered includes:
- fire control
- power distribution
- HV sub-stations
- emergency exit
- cross/egress passage ventilation
- incident detection and traffic monitoring
- incident response management
- building service control system
UGL is one of the only Australian infrastructure construction company that maintains a dedicated in-house engineering capability of its size, allowing the development and application of the innovative approaches seen in this project.
The efficient and effective delivery of the control and communications system contributed significantly to the tunnel opening seven months ahead of the original project schedule. Since opening, the tunnel has been well patronised, with an average of approximately 35,000 trips per working day recorded in 2017.
Due to the outstanding performance of the tunnel’s communication and control system, UGL was awarded the Engineering Excellence Award for 2012.
Key outcomes included:
- UGL’s innovative approach, in combination with our in-house multi-disciplined skill set, allowed ‘whole-of-facility’ system integration
- all the diverse sub-systems necessary for safe and reliable tunnel operation were integrated to provide a single, consistent human-machine interface for the operators and maintainers
- improved ease-of-use, which provided a higher level of automated response, further increasing the level of public safety